This book contains a classroom-tested approach to the teaching of problem solving to all students in Grades 4-6, regardless of ability. Information on problem solving in general is provided, then mathematical problems on logic, whole numbers, number theory, fractions, decimals, geometry, ratio, proportion, percent, probability, sets, and pre-algebra are presented. Answers to all problems are included. A problem-solving portfolio, a math myth's exercise, a matrix of problem-solving concepts, and a matrix of problem-solving strategies are appended. (ASK)